<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <h1>首页</h1>
{#    yy只是个前缀#}
    <img src="/static/640.jpg">
    <img src="{{ url_for('static',filename='640.jpg') }}">

</body>
</html>